The present invention is generally directed to an ink jet printing apparatus and imaging processes thereof. More specifically, the present invention is directed to color thermal ink jet printers and printing processes which enable, for example, gray scale color imaging with minimal additional cost and or reconfiguration of, for example, conventional four color or process color thermal ink jet imaging processes and printing apparatus. Even more specifically, the present invention is directed to thermal ink jet imaging processes which provide, for example, ink jet imaging processes that include selectively accomplishing a first jetting of one or more inks from, for example, a four color ink jet set, such as cyan, magenta, yellow, and black (C, M, Y, B), to from a first pixel, and thereafter accomplishing a second jetting over a portion of the resulting first pixel with xe2x80x9cheliosingxe2x80x9d ink formulation to produce a xe2x80x9cheliosedxe2x80x9d pixel which heliosed pixel exhibits a whitened, lightened, or brightened appearance to an observer. The heliosing ink formulation can be, for example, an obscurant formulation, a bleachant formulation, a penetrant formulation, and compatible mixtures or combinations thereof. The process can be accomplished in the alternative reverse order to achieve comparable heliosed pixel effects. The processes of the present invention can be further accomplished, for example, either selectively or comprehensively, over a large array of pixels to produce, in the aggregate, heliographic images with value added image properties as disclosed and illustrated herein.
In U.S. Pat. No. 4,680,645 issued Jul. 14, 1987, to Dispoto, et al., there is disclosed the capability of varying sizes of a dot in a printer to provide a gray scale image of superior quality. Errors in gray level are used to modulate the sizes of the dots in producing the image.
In U.S. Pat. No. 4,630,076, issued Dec. 16, 1986 to Yoshimura, there is disclosed a color ink jet system printer of the ink-on-demand type which includes four orifices for emitting yellow ink droplets, magenta ink droplets, cyan ink droplets and black ink droplets, and an additional orifice for emitting white or transparent ink droplets. The white or transparent ink droplets are emitted in the thinned printing mode in a manner that the white or transparent ink droplets overlap on printed dots printed by the yellow, magenta, cyan and/or black ink droplets. By overlapping the white or transparent ink droplets on the previously printed dots, the previously printed dots bleed and spread to provide a light tone image superpixel.
In U.S. Pat. No. 5,552,811, issued Sep. 3, 1996, to Kurata, et al., there is disclosed a cleaning member for use in ink jet printing including a rinsing liquid that is discharged from a nozzle onto the cleaning member to wipe the discharging port surface of the liquid discharging apparatus. There is also disclosed the possibility of a liquid discharging head which discharges a bleaching agent to decolor ink, for example, in addition to the liquid discharging head to discharge ink to a printing medium. This is used to locally bleach the part which is deeply dyed by ink.
In U.S. Pat. No. 4,413,266, issued Nov. 1, 1983, to Aviram, et al., there is disclosed an apparatus for ink jet printing under the control of electronic circuitry and ink jet printing under the control of an operator, for example, a typewriter. Broadly, the technology presented in accordance with the principles of this invention utilizes an ink eradicator which removes indicia of the ink by chemical reaction. The character of the eradicator fluid is such that another fluid may be utilized either together therewith or separately to neutralize the residue from the chemical reaction so that printing can readily be accomplished in the location where erasure has occurred. Specifically, practice of this invention is contemplated with means that applies the eradicator fluid over the location on a surface where printing has occurred by ink jet droplets as well as over an entire area thereon within which there is ink jet printing for which a change is to be achieved. For exemplary embodiments of this invention, the eradicator fluid is applied by a wick from a reservoir and the chemical reaction is enhanced by heating the location for the erasure by an external heating means.
In U.S. Pat. No. 5,922,115, issued Jul. 13, 1999, to Sano et al., there is disclosed a decolorizable ink consisting of an ink dispersed in a solvent, the ink composition comprising a color former, a developer and a decolorizer, wherein the color former and developer are in a colored state by interaction between them and the decolorizer has a property to dissolve preferentially the developer when the ink composition is melted.
In U.S. Pat. No. 5,710,195 issued Jan. 20, 1998, to Subbaraman, et al., there is disclosed methods for creating opaque indicia on substrate surfaces and to non-pigmented, moisture-free, jet ink compositions containing only solvents and solvent soluble resins and dyes that exhibit the acceptable characteristics of opacity, contrast, adhesion and machine compatibility. The compositions contain a combination of film forming resins of varying molecular weights of a dry resin solids percentage between 8 and 15%. The resins are chosen from the following: nitrates of cellulose; acrylics; alkyds; vinyl acetate-vinyl chloride copolymers; and styrene acrylic. The quantities of resin are chosen according to the desired viscosity, adhesion strength of film on the subject substrate and the degree of shearing of the drying resin mixture. An optimum balance of adhesion and opacity is stoichiometrically obtained. The differential solubilities of the resins in the solvent-blend is the prime moving factor of the opacifying action. The use of acid dyes and basic salts that exhibit fluorescence is considered and used in the formulations to enhance the visibility and contrast of the resultant opacified dried state of resin solids on the substrate surface. The use of specific plasticizers are another feature of this invention. Plasticizers are used in the ink jet composition to increase the flowability of the composition and also increase the tensile strength and adhesion of the ink to the substrate to which it is applied. The principle of this invention is that a water-free, multi-solvent and multi-resin jet ink which characteristically forms micro laminate miscelli and plasticizers is found to have good adhesion and opacity, and can be used to mark code and indicate non-absorbent dark substrates.
In U.S. Pat. No. 5,674,923, issued Oct. 7, 1997, to Subbaraman, et al., there is disclosed non-pigmented opaque jet ink compositions and methods of creating opaque indicia with temporarily varying opacity which method includes applying the ink composition to a substrate; drying the ink composition to create an indelible, abrasion resistant, climatically stable and opaque indicia on the substrate; wetting the indicia with polar aqueous liquid to decrease the opacity of the indicia; and drying the indicia to increase the opacity of the indicia.
In U.S. Pat. No. 5,607,999, issued Mar. 4, 1997, to Shimizu, et al., there is disclosed water-based recording inks, including white inks, comprising water, a pigment, a water-soluble homopolymer and a copolymer having both a hydrophobic portion and a hydrophilic portion. The inks can provide a print having excellent density, light fastness and water resistance. Furthermore, the water-based recording ink has such various properties necessary for use as an ink jet recording ink that it does not clog a fine ejection nozzle, has excellent rubbing resistance and setting to dry in the print, is free from aggregation or settlement of solid matter, such as a pigment particle, and exhibits no change in the properties of the ink even when stored at a high temperature or a low temperature for a long period of time and can be redispersed by stirring or further addition of a solvent even when the pigment once aggregated.
In U.S. Pat. No. 5,543,177, to Morrison et al., issued Aug. 6, 1996, there is disclosed marking materials containing retroreflective fillers, for example, glass beads in white inks, and processes for the use thereof. In one embodiment, images containing retroreflective fillers are generated on paper by any suitable means, such as electrostatic imaging and development with either dry or liquid developers, ink jet printing, strip-out development processes, or the like, and the images thus generated are used to control a document reproduction system.
In U.S. Pat. No. 4,880,465, issued Nov. 14, 1989, to Loria, et al., there is disclosed non-pigmented inks suitable for use in ink jet printing comprising a resin component, hollow or non-hollow microspheres, and a suitable carrier vehicle. The hollow microspheres contain a central void region filled with a liquid capable of diffusing through the walls of the microspheres and have an inside diameter from about 0.1 to about 0.5 micron and an outside diameter from about 0.4 to about 1 micron.
In U.S. Pat. No. 4,680,058, to Shimizu et al., issued Jul. 14, 1987, there is disclosed a method where dark or black print articles are ink-jet printed with a white ink composition comprising at least a white pigment having a particle size of less than 3 micrometer, a solvent and a binder resin, resulting in good print stability. The white ink composition has a good dispersion stability, a good redispersability, and no nozzle clogging. White pigments include titanium oxide, zinc white, lithopon, lead white, zinc sulfide, white basic lead sulfate, zirconium oxide, antimony white, and tin oxide, which can be used alone or in their mixture.
In U.S. Pat. No. 5,833,743, issued Nov. 10, 1998, to Elwakil, there is disclosed a method of printing an image on a substrate with an ink jet printer, the method including the step of ejecting a plurality of discrete portions of ink from the ink jet printer toward the substrate, the ink including at least three different inks with each ink of each different pair of inks containing either different dyes or different concentrations of the same dye, and the step of sequentially forming a plurality of layers of ink dots on the substrate using the discrete portions of ink, with adjacent layers having overlapping ink dots formed of different inks, the plurality of layers of ink dots constituting the image, and the image fully covering all portions of the substrate beneath the image.
The aforementioned and hereinafter cited patents are incorporated by reference herein in their entirety.
There remains a need for aqueous ink compositions and thermal ink jet and related ink printing processes which can provide gray scale color printing and high resolution color images at low total cost for imaging materials and imaging hardware. These and other needs are provided for in embodiments of the present invention.
The ink compositions and processes of the present invention are useful in many applications including imaging and printing processes, including color printing, for example, thermal ink jet (TIJ), bubble jet, ballistic, and acoustic ink printing systems, including digital systems.
Embodiments of the present invention, include:
A process comprising:
jetting at least one ink from a color ink set onto a substrate to form a first pixel; and
jetting a heliosing ink onto the first pixel to form a heliosed pixel, wherein the first pixel is substantially free of resolution diminution in the heliosed pixel;
A process comprising:
jetting a heliosing ink onto a substrate to form a first pixel; and
jetting at least one ink from a color ink set onto the first pixel to form a heliosed pixel, wherein the resolution in the heliosed pixel is substantially the same as the resolution in the absence of the heliosing ink; and
An ink jet recording apparatus with an ink jet deposition system which jets inks in accordance with the above heliographic processes to afford heliographic images.
These and other features are illustrated herein.